[Clinico-morphological characteristics of leptospirosis]

Observations in 5 patients dying with leptospirosis (at 6-30 days after the onset) caused by leptospira of the Hebdomadis serogroup are described. Bright jaundice developed due to severe serous liver centrilobular edema with pronounced dissociation of the liver cell bands, cholestasis, and cloudy swelling of hepatocytes. Albuminuria, oliguria, and uraemia were caused by acute tubular and interstitial nephritis. Hemorrhagic diathesis with small bleedings in the skin, mucous and serous membranes was associated with the impairment of permeability of microcirculatory vessels. Focal necroses of skeletal muscles, myocardiodystrophy, and focal myocarditis, serous leptomeningitis were also seen. Few leptospirae could be detected extracellularly (often attached to the outer host cell membranes) by Warthin-Starry's method of silver impregnation of paraffin sections and by indirect immunofluorescence, much more rarely could they be demonstrated by Levaditi's method of silver impregnation of pieces of the viscera. Most leptospirae were present in the liver in the case of death on the 6th day when no antibodies were yet present in the blood. Since the 9th day when the antibodies did appear, leptospirae gradually disappeared from the liver and were found in the kidneys. It is suggested that some leptospiral cytotoxic products play a role in the pathogenesis of leptospirosis.